Child resistant closure with improved assembly

ABSTRACT

The present invention relates to child-resistant closures, and more particularly to child-resistant closures with multiple caps, engaged by two oppositely acting locking system, which offer advantages over the prior art by enabling easier opening, yet remains child-resistant.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority from an Indian Patent Application IN 331/CHE 2009 filed on Feb. 16, 2009.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

BACKGROUND OF THE INVENTION

To reduce the number of accidental incidents, which may result due to access of unsafe medicine by children, containers are properly closed by means of closures. The most important attribute of closures is security as it controls access to the product. Various closures having tamper proof and child resistant features are developed to control access to the contents of the container by overcoming accidental incidents and to improve upon existing features of closures.

(1) Field of the Invention

The present invention relates to child-resistant closures, and more particularly to child-resistant closures with multiple caps, engaged by two oppositely acting locking system, which offer advantages over the prior art by enabling easier opening, yet remains child-resistant.

(2) Description of Related Art

Today, child-resistant closures are very important for the safety of children. As used herein, use of the term “child-resistant closure” is consistent with 16 CFR 1700 and refers generally to the inability of a younger child's or person with a younger child's strength and/or manual dexterity to open a closure 85% of the time within a given amount of time without a demonstration of how to open the closure, or 80% of the time with such a demonstration.

There are many caps of the type having an inner cap adapted to threadedly engage the neck portion of a container and an outer cap fixedly attached over the inner cap to prevent external access thereto. Upon pushing the outer cap toward the inner cap, the two caps engage in some manner so as to produce rotation of the inner cap with the outer cap and allow unthreading thereof. (Examples of such caps are disclosed in U.S. Pat. Nos. 2,964,207, 3,374,912, 3,394,829, 3,396,864, 3,764,033, 3,853,236, 3,857,505 and 3,944,102. One problem with many of such closures is that they cannot be applied with conventional capping machinery.

The most common closures, which have proven to work well, are caps, which require two or more concurrent motions in order to open them. For example, one such design is the “push-and-turn” closure. This type of closures can only be opened by simultaneously pushing downward on the cap while turning it.

Examples of “push-and-turn” designs are disclosed in U.S. Pat. Nos. 4,319,690 and 4,394,916. These patents describe a typical two-piece, ramp and ratchet lugs design. A plurality of ratchet lugs on one cap project towards a plurality of corresponding ramps on the opposite cap. Generally, the ramps and lugs engage each other when turned in a fastening direction such that the two caps turn in tandem. The ratchet lugs are integrally formed and circularly disposed about an annular stop member. Both the ratchet lugs and the stop member are concentrically arranged about the center of the circular end wall.

U.S. Pat. No. 4,319,690 further describes a closure with a flange of the top pane extending radially outwardly from the periphery of the web-like portion and a plurality of upwardly extending nibs. Integrally formed with the nibs are an equal number of upwardly extending stop ribs. The stop ribs prevent the ratchet lugs of the outer cap from overstressing and permanently deforming the dome-shaped top panel.

U.S. Pat. No. 4,723,685 discloses a two-piece child-resistant closure having a molded plastic inner and outer component, the inner component having a double ended liner retention bead that projects radially inwardly from the inside of an annular skirt portion to retain a sealing liner in a position that is adjacent to the underside of a top panel portion, which further having a helically extending thread that projects radially inwardly from the annular skirt portion, the thread having an uppermost portion with a 0° helical arch.

U.S. Pat. No. 4,997,096 discloses a child resistant closure comprising an outer shell having a base wall and a peripheral skirt and an inner shell having a base wall and a peripheral skirt telescoped within the outer shell.

U.S. Pat. No. 6,206,216 discloses a child-resistant cap assembly, comprising an inner cap with at least one inner cap projection having a complex angled surface and an outer cap, wherein said outer cap has a retaining mechanism which engages said inner cap such that said inner cap and said outer cap are freely rotatable relative to each other, and wherein said outer cap has at least one outer cap projection, wherein said outer cap projection and said inner cap projection engage by radial contact over a length on said complex angled surface when unfastening the cap assembly.

Even though the prior art disclose child resistant closures, still there is need to develop an improved child resistant closure which is difficult to open by children while simultaneously allowing others, such as seniors, to open easily.

OBJECTIVE OF THE INVENTION

Accordingly, the main objective of the present invention is to provide a child-resistant closure, and more particularly child-resistant closures with multiple caps, which engaged by two oppositely acting locking system, which offer advantages over the prior art by enabling easier opening, yet remains child-resistant.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the main embodiment of the present invention is to provide a child-resistant cap assembly, comprising:

a) an inner cap having a dome-shaped top panel having peripheral arches and central ratchets with the inner side consisting of elevated threads and b) an outer cap having elevated projections complimentary to the projections of top surface of inner cap, so as to match with each other leading to a locking arrangement which allows the inner cap to move by the force applied on the outer cap in clockwise direction, the elevated projections of outer closure rides over the gradational elevations of inner cap causing slippage of the outer closure over the inner closure leading to free movement, wherein the closure does not contain any stop member.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1( a) represents top view of inner cap.

FIG. 1( b) represents sectional view of inner cap showing circularly arranged threads A.

FIG. 1( c) represents bottom view of inner cap.

FIG. 1( d) represents the inner cap showing the arrangement of ratchet lugs.

FIG. 1( e) represents the 3D view of the inner cap.

FIG. 2( a) represents the bottom view of outer cap.

FIG. 2( b) represents the front view of outer cap.

FIG. 2( c) represents the top view of outer cap.

FIG. 2( d) represents sectional view of outer cap along with center of projection A.

FIG. 3( a) represents closure closing.

FIG. 3( b) represents closures opening.

FIG. 4( a) represents bottles closing by means of closures.

FIG. 4( b) represents bottles opening by means of closures.

FIG. 5( a) represents the outer 3D view of outer cap.

FIG. 5( b) represents the top view of outer cap by showing the detail of engraving.

DETAILED DESCRIPTION OF THE INVENTION

The inner cap comprises outer and inner side, wherein the outer side is engaged in outer cap and inner side is attached with the container.

In another embodiment, the outer side of the inner cap consists of two elevated circular projections, one on the center and one on the peripheral. The elevated projection at the center consists of at least two pieces of helical structures, which progressively increase in height and form an angle ranging from 0-180° with the base called as ratchet lugs which are arranged circularly to form an inner cam system.

The elevated projection at the peripheral consists of at least two arches, dimensions of which are equally distributed with gap between two arches. The arches are look like pockets, which are formed with rigid border of plastic material having an empty space within the border. One end of the arch is little sloppy in the direction of progressive arches at center and other end form an angle ranging from 0-180° with the base meant for peripheral locking system.

The top portions of the inner cap are convex or dome-shaped in nature, which give resilient effect. The inner sides of the inner cap consist of threads, which encompasses on the complimentary threads of container and ensure capping.

The dome-shaped top panel provides a biasing force to maintain the inner and outer caps in a second axial position. Downward pressure on the outer cap will overcome the bias of the dome-shaped top panel to place the inner and outer caps in a first axial position wherein the inner and outer caps are coupled thereby allowing rotation of the inner and outer caps in unison to allow removal of the closure.

The outer cap comprises outer side and inner side, wherein the inner side is fixed with the outer side of the inner cap.

In another embodiment, the inner side of outer cap consists of at least two projections at periphery, wherein each projection is pocket type made with rigid border of plastic material having an empty space within the border and further the width of which are less than the gap between the peripheral arches of top portions of inner cap. The central surface of the inner side of the outer cap consists of at least two pieces helical structures, which progressively increase in height and form an angle ranging from 0-180° with the base called as ratchet lugs which are arranged circularly to form an outer cam system. Further, the outer cap has serrations running circularly in the outer diameter in front side of the outer cap.

The closure assembly can be done either by fixing the inner component inside the outer component or by fixing the outer component to the top of inner component.

Yet another embodiment, the child resistant closure has two oppositely acting locking system i.e. outer periphery locking system and center cam system. Center cam system has been used to provide easy closing of the closure on the container without applying much torque. Similarly, while opening, specially designed outer periphery locking system doesn't allow the children to open the closure with any force or any kind of tampering to be done on the closure in any direction.

In an embodiment of the present invention, there is a provided a child resistant closure having an inner cap adapted to be loosely retained within the outer cap of a safety closure to allow relative rotary movement between the inner cap member. The inner cap having a dome-shaped top panel comprising six peripherally arranged arches which are equally distributed in the gap between the two arches and six centrally placed helical progressive structures or ratchet lug which progressively increase in height and form right angle with the base and arranged circularly to form central cam system. Similarly, the outer cap comprises six projection or arches at periphery, the width of which are less than the gap between the peripheral arches of top portion of inner cap and six helical progressive structures called as ratchet lug, which are complimentary to the projection present in the inner cap, wherein the closure does not contain stop member.

The inner and outer cap are joined by means of two oppositely acting system, i.e.

-   i) center cam system, which provide easy closing of the closure on     the container without applying much torque and -   ii) specially designed outer periphery locking system, which doesn't     allow the children to open the closure with any force or tampering     on the closure in any direction.

Accordingly with reference to FIG. 1 (a) the inner cap 20 shows two circular projections arranged in two circular surface 1 and 2, which comprise peripherally arranged six piece in arches or pockets 3 which are equally distributed with gap between two arches and arranged within first circular surface 1 and centrally placed six helical progressive structures or ratchet lugs 4 which are arranged in progressively increase in height in the second circular surface 2 called as center cam. The ratchet lugs are progressively increase in height and form a right angle with the base as shown in FIG. 1( d). The bottom part of the inner cap comprises outer diameter 5, which further comprises notches 6 and thread 7 as shown in FIG. 1( c).

Similarly, with reference to FIG. 2 (a) the outer cap 30 shows an outer circle 8 where six projections 10 are arranged peripherally having rotator rib, wherein the width of each projection is less than the gap between the two complementary projections present in the top portion of the inner cap and further the inner circle 9 has six centrally arranged helical progressive structures or ratchet lugs 11, which is complementary to outer side of the inner cap and attached with the inner cap by the application of pressure at the top of the closure. The cap further contains inner rotating ring 12 arranged circularly in the inner surface of the outer cap. The outer cap further comprises outer serration 13 arranged circumferrally in the outer side of the outer cap as shown in FIG. 2( c).

The inner cap 20 and outer cap 30 are fixed together by applying pressure to form an assembly of outer and inner cap represented by 40 as shown in FIG. 3( a). To close the container with the cap, the assembled cap need to be placed into the container neck and force (torque) is applied at the top of the closure in clock wise direction leading to the engagement of the complimentary elevations which then engaged to the container threads and ensure closing the cap; while attempting to open the closure as shown in FIG. 3 (b) that is by unscrewing the closure in anti clock wise direction, the elevated projections of outer closure rides over the gradational elevations of inner cap causing slippage of the outer closure over the inner closure leading to free movements, the coupling between outer side of inner closure and inner side of outer closure occurs only when downward pressure is exerted on the top of the outer closure encompassing the inner closure to move on the threads of the container leading to unscrewing of the closure while rotating in anticlockwise direction with simultaneous downward pressure on the top of the outer closure.

Due to convexity of the top surface of the inner closure and the resilient effect, the engagement/coupling occur only when certain amount of pressure is exerted, which is difficult for the children to apply. The design of the closure ensures that the engagement of the coupling projections will not occur until right amount of downward pressure is exerted simultaneously with the rotational anti clockwise movement which makes it more effective in terms of making the design difficult to open for children.

FIG. 4 (a) represents an outer cap and inner cap assembly 40, which has suitably, configured threads that can be mounted on the container 41.

The closure is molded as outlined wall/partially filled to fully fill with materials.

The child resistant closure mainly formed from a plastic material such as polyvinyl chloride (PVC), though differing materials such as low or high density polyethylene, polypropylene, polystyrene, polyester teraphthalate (PET), nylon and the like may be similarly substituted. Further, according to various alternative aspects of the present invention, inner cap and outer cap may each suitably be formed from differing materials. For example, it may be desirable to form outer cap from a more rigid material than inner cap so that outer cap is more easily gripped by the user or so that inner cap has the ability to resiliently deform as desired when cap assembly is used.

Yet another embodiment of the present invention, there is provided an opening instruction on the outer part of the outer cap in the form of written text as well as pictorial form. The opening instruction is debossed on English language and also same is represented in pictorial format that make an advantage that even a non English speaking user can be communicated through the pictorial representation as shown in FIGS. 5( a) and 5(b).

The specific designs exemplified in the invention are not intended to limit the scope of the invention. It is obvious to those skilled in the art to find out various alternations and modifications in the construction and arrangement of parts without departing from the scope and spirit of the invention.

DRAWINGS

FIGS. 1 thru 5 are shown on pages 1 through 6. 

1. A child-resistant cap assembly, comprising: a) an inner cap having a dome-shaped top panel having peripheral arches and central ratchets with the inner side consisting of elevated threads and b) an outer cap having elevated projections complimentary to the projections of top surface of inner cap, so as to match with each other leading to a locking arrangement which allows the inner cap to move by the force applied on the outer cap in clockwise direction, the elevated projections of outer closure rides over the gradational elevations of inner cap causing slippage of the outer closure over the inner closure leading to free movement, wherein the closure does not contain any stop member.
 2. The child-resistant cap assembly as claimed in claim 1, wherein the outer side of the inner cap consists of two elevated circular projections, one on the center and one on the peripheral.
 3. The child-resistant cap assembly as claimed in claim 2, wherein the central elevated projection consists of at least two pieces of helical structures, which progressively increase in height and form an angle ranging from 0-180° with the base.
 4. The child-resistant cap assembly as claimed in claim 2, wherein the peripheral elevated projection consists of at least two arches, dimensions of which are equally distributed with gap between two arches.
 5. The child-resistant cap assembly as claimed in claim 4, wherein the peripheral arches are look like pockets, which are formed with rigid border of plastic material having an empty space within the border.
 6. The child-resistant cap assembly as claimed in claim 4, wherein one end of the arch is little sloppy in the direction of progressive arches at center and other end form an angle ranging from 0-180° with the base meant for peripheral locking system.
 7. The child-resistant cap assembly as claimed in claim 1, wherein the inner side of outer cap consists of at least two projections at periphery, wherein each projection is pocket type made with rigid border of plastic material having an empty space within the border and further the width of which are less than the gap between the peripheral arches of top portions of inner cap.
 8. The child-resistant cap assembly as claimed in claim 1, wherein the central surface of the inner side of the outer cap consists of at least two pieces helical structures, which progressively increase in height and form an angle ranging from 0-180° with the base
 9. The child-resistant cap assembly as claimed in claim 1, wherein the downward pressure on the outer cap will overcome the bias of the dome-shaped top panel to place the inner and outer caps in a first axial position wherein the inner and outer caps are coupled thereby allowing rotation of the inner and outer caps in unison to allow removal of the closure.
 10. The child-resistant cap assembly wherein the inner and outer cap are joined by means of two oppositely acting system, comprising i) center cam system, which provide easy closing of the closure on the container without applying much torque and ii) specially designed outer periphery locking system, which doesn't allow the children to open the closure with any force or tampering on the closure in any direction. 